It’s a huge win for Baauer (Harry Rodrigues), a 23-year-old Brooklyn producer, who released the song on Jeffree’s, a division of Diplo’s Mad Decent label, last May — initially, for free. Until recently, “Harlem Shake” had almost zero airplay and not many more sales. According to Nielsen SoundScan, the single jumped from 1,000 sales a week to 18,000 in the week that the “Harlem Shake” videos went viral, and this week it sold 262,000 downloads, a 1,359 percent increase. Baauer’s chart coup ought to net his song more airtime — in fact, it’s turning up on Hot97 and other mainstream outlets now — and still more sales.

But Baauer, who told The Daily Beast he never expected his song to turn into a full-blown meme, didn’t just get lucky; he got really lucky. It’s like he scored big on a scratch-and-win card and pocketed all but a single dollar, which he invested in a Megabucks ticket — and then won that, too.

Because the same week that Baauer’s eight-month-old song broke, thanks to its viral popularity on YouTube, Billboardimplemented a new methodology for tabulating the Hot 100. Whereas the chart had previously been determined by a formula including terrestrial radio, on-demand audio streaming, online radio streaming, and Nielsen SoundScan’s digital download (and physical singles) sales reports, Billboard’s new rules now factor into the mix — yeah, you got it — YouTube plays.

It’s like when you’re thinking about a plate of shrimp, and somebody says “plate,” or “shrimp,” or “plate of shrimp.” (Chalk it up to the lattice of coincidence.)

In any case, Baauer’s unbelievably fortuitous breakthrough is also a significant boon for Billboard, which was presented with the perfect PR nugget to announce its updated chart methodology. With radio increasingly out of touch with listeners and viral culture going Gangnam-busters, the “Harlem Shake” No. 1 gives Billboard a chance to prove that it’s still got its finger on the pulse of popular culture. (And, since it’s the Hot 100, Baauer’s victory is a better look for Billboard than when Psy topped Billboard’s Rap Songs chart.)

The biggest beneficiary here may be YouTube. Gaining a foothold in the Hot 100’s data matrix grants legitimacy to the streaming-video behemoth, officially confirming it as a major player in the music industry. That might seem ironic, since YouTube is also a big part of the reason that people don’t buy music any more. But, as Billboardpointed out last week, new services allow labels like Mad Decent to automatically identify and monetize any instances of trademarked content used on YouTube. Artists may be earning only fractions of a penny, but with tens of thousands of user-generated “Harlem Shake” videos tallying up hundreds of millions of views, those fractions add up.

So it’s a win-win-win-win for Baauer, Mad Decent, Billboard, and YouTube. It couldn’t have worked out better for them if they’d come up with the whole thing themselves. Someone really ought to be sending Filthy Frank, the YouTuber who kicked off the “Harlem Shake” phenomenon, a token of their esteem. A gift certificate to Red Lobster might do.